Ore-grinding mill



(No Model.)

B. 0. GRANT.

Ore Grinding Mill.

No. 234,027. Patented Nov. 2,1880.

IHIFII WITNESSES INVENTOR ATTORNEYS.

N-PETERS. PHOTO-LITHOGRAPHER. WASHINGYON, D C.

UNITED STATES PATENT OFFICE.

ROYAL O. GRANT, OF MIDDLEPORI, OHIO.

ORE-GRINDING MILL.

SPECIFICATION forming part of Letters Patent No. 234,027, dated November2, 1880.

To all whom it may concern:

Be it known that I, ROYAL 0. GRANT, of Middleport, in 'the county ofMeigs and State of Ohio, have invented a new and useful Improvement inOre Crushing, Grinding, and Pulverizing Mills; and I do hereby declarethat the following is afull, clear, and exact description of the same.

The object of my invention is to provide an improved machine forcrushing, grinding, and pulverizing the valuable ores in order that bycomminution the metallic portion may be separated from the gangue.

The machine I have devised is of that class in which a tapering orcone-like shell revolves around a core of corresponding shape.

The features of novelty and improvement are the means hereinafterdescribed for lessenin g the friction between the core and shell andalso pnlverizin g the ore, and for facilitating the discharge of thepulverized ore from the machine.

In accompanying drawings, forming part of this specification, Figure 1is partly a side view and partly a section ofmy improved mill. Fig. 2 isa plan .view of a portion of the mill with the shell removed, the conebeing in section.

The tapered or conical truncated shell A has a flaring top or rim, whichforms the hop per for receiving the ore to be crushed, ground, andpulverized. The core B has a like tapered shape, and both shell and coreare lined with ribbed chilled iron or steelified plates that are securedin place by screws and lugs. The shell and core have also horizontal orbase portions a b, which are similarly provided with detachablegrinding-plates and with coincident circular grooves to accommodate therollers O. The latter have rounded edges, and are mounted loose on shortshafts, whose ends enter and are secured in holes in the oppositecircular coincident bands at e, that revolve or slide on the bed-plateand core B. Thus half the thickness of the rollers lies in the groove inthe bed-plate b and the other half projects into the coincident groovein the base a of shell A. The latter is therefore supported on saidrollers as it rotates around the core (No model.)

B. The core has a stem or shaft, D, which extends vertically from itsupper end, and passes through a four-armed cross-head spider, E,attached to the top of the shell. A screw-nut, f, is applied to the endof the stem D, and metal washers g and elastic blocks or spiral springsh are placed between the nut and cross-head.

By these devices the shell A may be held down on the rollers O with ayielding press" ure. By adjusting the nut fthe downward pressure of theshell A can be varied at will, and the ore thus crushed and ground moreor less finely. At the same time the slight vertical movement permittedby the spring it allows the shell A to accommodate itself somewhat tothe variation in size or quantity of pieces of ore descending from thehopper. The shell A is rotated by a gear, F, which is keyed on ahorizontal driving-shaft, G, and meshes with a gear or toothed plate, H,attached horizontally to the base of the shell.

In order to keep the base of the shell A in proper position-21 0.,concentric with the core B--I employ friction-rollers is, mounted looseon studs fixed in the bed-piece. The friction of the shell A with therollers G and the friction of the latter with the bottom of the circularchannel or groove in the bed-piece causes the rollers and bands 01 e totravel around the core at the same time with the shell, although thebands will not always move at the same speed. The ore is thereforepulverized by the action of the rollers O on the same in such channel orgroove,'and thus the rollers are made to subserve an important functionin addition to supporting the shell A and relieving friction.

As a means of discharging the pulverized ore from the channel, I employscrapers or pushers I, which are hinged onto the rings d 0 rotatingshell and traveling-rollers (J, of the hinged plates, having their loweredges serrated to adapt them for loosening, the coinpacted ore, and thehinged plates for scraping the bottom of the groove and removing the orethus loosened, all as shown and described, for the purpose specified.

2. The combination, with the core and the rotating shell and bed-piece,grooved as specitied, of rollers G, journaled upon the traveling 10bands (1 c, all as shown and described, to operate as specified.

ROYALCLARK GRANT. Witnesses E. R. GRANT, J. B. FISHER.

